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1.
Front Cell Infect Microbiol ; 14: 1405333, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39149421

RESUMEN

Introduction: Streptococcus pneumoniae (the pneumococcus) effectively colonizes the human nasopharynx, but can migrate to other host sites, causing infections such as pneumonia and sepsis. Previous studies indicate that pneumococci grown as biofilms have phenotypes of bacteria associated with colonization whereas bacteria released from biofilms in response to changes in the local environment (i.e., dispersed bacteria) represent populations with phenotypes associated with disease. How these niche-adapted populations interact with immune cells upon reaching the vascular compartment has not previously been studied. Here, we investigated neutrophil, monocyte, and platelet activation using ex vivo stimulation of whole blood and platelet-rich plasma with pneumococcal populations representing distinct stages of the infectious process (biofilm bacteria and dispersed bacteria) as well as conventional broth-grown culture (planktonic bacteria). Methods: Flow cytometry and ELISA were used to assess surface and soluble activation markers for neutrophil and monocyte activation, platelet-neutrophil complex and platelet-monocyte complex formation, and platelet activation and responsiveness. Results: Overall, we found that biofilm-derived bacteria (biofilm bacteria and dispersed bacteria) induced significant activation of neutrophils, monocytes, and platelets. In contrast, little to no activation was induced by planktonic bacteria. Platelets remained functional after stimulation with bacterial populations and the degree of responsiveness was inversely related to initial activation. Bacterial association with immune cells followed a similar pattern as activation. Discussion: Differences in activation of and association with immune cells by biofilm-derived populations could be an important consideration for other pathogens that have a biofilm state. Gaining insight into how these bacterial populations interact with the host immune response may reveal immunomodulatory targets to interfere with disease development.


Asunto(s)
Biopelículas , Neutrófilos , Activación Plaquetaria , Streptococcus pneumoniae , Biopelículas/crecimiento & desarrollo , Humanos , Streptococcus pneumoniae/inmunología , Neutrófilos/inmunología , Monocitos/inmunología , Monocitos/microbiología , Infecciones Neumocócicas/microbiología , Infecciones Neumocócicas/inmunología , Plaquetas/microbiología , Leucocitos/inmunología , Citometría de Flujo , Adulto , Femenino , Masculino
2.
Front Microbiol ; 15: 1406190, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39101559

RESUMEN

Challenges from infections caused by biofilms and antimicrobial resistance highlight the need for novel antimicrobials that work in conjunction with antibiotics and minimize resistance risk. In this study we investigated the composite effect of HAMLET (human alpha-lactalbumin made lethal to tumor cells), a human milk protein-lipid complex and amoxicillin on microbial ecology using an ex vivo oral biofilm model with pooled saliva samples. HAMLET was chosen due to its multi-targeted antimicrobial mechanism, together with its synergistic effect with antibiotics on single species pathogens, and low risk of resistance development. The combination of HAMLET and low concentrations of amoxicillin significantly reduced biofilm viability, while each of them alone had little or no impact. Using a whole metagenomics approach, we found that the combination promoted a remarkable shift in overall microbial composition compared to the untreated samples. A large proportion of the bacterial species in the combined treatment were Lactobacillus crispatus, a species with probiotic effects, whereas it was only detected in a minor fraction in untreated samples. Although resistome analysis indicated no major shifts in alpha-diversity, the results showed the presence of TEM beta-lactamase genes in low proportions in all treated samples but absence in untreated samples. Our study illustrates HAMLET's capability to alter the effects of amoxicillin on the oral microbiome and potentially favor the growth of selected probiotic bacteria when in combination. The findings extend previous knowledge on the combined effects of HAMLET and antibiotics against target pathogens to include potential modulatory effects on polymicrobial biofilms of human origin.

3.
PLoS One ; 19(8): e0307573, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39110759

RESUMEN

Streptococcus pneumoniae is a bacterium of great global importance, responsible for more than one million deaths per year. This bacterium is commonly acquired in the first years of life and colonizes the upper respiratory tract asymptomatically by forming biofilms that persist for extended times in the nasopharynx. However, under conditions that alter the bacterial environment, such as viral infections, pneumococci can escape from the biofilm and invade other niches, causing local and systemic disease of varying severity. The polyamine transporter PotABCD is required for optimal survival of the organism in the host. Immunization of mice with recombinant PotD can reduce subsequent bacterial colonization. PotD has also been suggested to be involved in pneumococcal biofilm development. Therefore, in this study we aimed to elucidate the role of PotABCD and polyamines in pneumococcal biofilm formation. First, the formation of biofilms was evaluated in the presence of exogenous polyamines-the substrate transported by PotABCD-added to culture medium. Next, a potABCD-negative strain was used to determine biofilm formation in different model systems using diverse levels of complexity from abiotic surface to cell substrate to in vivo animal models and was compared with its wild-type strain. The results showed that adding more polyamines to the medium stimulated biofilm formation, suggesting a direct correlation between polyamines and biofilm formation. Also, deletion of potABCD operon impaired biofilm formation in all models tested. Interestingly, more differences between wild-type and mutant strains were observed in the more complex model, which emphasizes the significance of employing more physiological models in studying biofilm formation.


Asunto(s)
Biopelículas , Streptococcus pneumoniae , Biopelículas/crecimiento & desarrollo , Streptococcus pneumoniae/fisiología , Streptococcus pneumoniae/metabolismo , Animales , Ratones , Poliaminas/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Infecciones Neumocócicas/microbiología , Proteínas de Transporte de Membrana/metabolismo , Proteínas de Transporte de Membrana/genética , Operón
4.
Europace ; 26(8)2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39056247

RESUMEN

AIMS: Short-term ambulatory electrocardiogram (ECG) monitoring is often used to assess premature atrial complex (PAC) and premature ventricular complex (PVC) frequency, but the diagnostic reliability is unknown. The objective of this study was to study the day-to-day variability of PAC and PVC frequency. METHODS AND RESULTS: We used 14-day full-disclosure mobile cardiac telemetry recordings without atrial fibrillation in 8245 US patients aged 17-103 years to calculate the diagnostic reliability of shorter ambulatory ECG recordings compared with 14-day averages. Over 14 days, 1853 patients had ≥500 PACs/day, 410 patients had ≥5000 PACs/day, and 197 patients had ≥10 000 PACs/day; 1640 patients had ≥500 PVCs/day, 354 patients had ≥5000 PVCs/day, and 175 patients had ≥10 000 PVCs/day. After 3 days, the estimated daily PAC frequency differed by ≥50% from the 14-day mean in 25% of patients; for PVCs, the corresponding duration was 7 days. Ten days of monitoring were needed to estimate PAC and PVC frequency within ±20% of the overall 14-day frequency in 80% of patients. For daily PAC and PVC frequencies ≥10 000, single-day estimation had a specificity of 99.3% [95% confidence interval (CI) 99.1-99.5] at a sensitivity of 76.6 (95% CI 70.1-80.4%) for PACs and a 99.6% (95% CI 99.4-99.7%) specificity at 79.4 (95% CI 72.7-85.2) sensitivity for PVCs. After 7 days, the sensitivity increased to 88.8% (95% CI 83.6-92.9) for PACs and 86.9% (95% CI 80.9-91.5%) for PVCs. CONCLUSION: While there is substantial daily variability across most PAC and PVC levels, findings of ≥10 000 PACs or PVCs are highly specific and do not need to be confirmed with longer recordings.


Asunto(s)
Complejos Atriales Prematuros , Electrocardiografía Ambulatoria , Complejos Prematuros Ventriculares , Humanos , Complejos Prematuros Ventriculares/diagnóstico , Complejos Prematuros Ventriculares/fisiopatología , Persona de Mediana Edad , Anciano , Reproducibilidad de los Resultados , Femenino , Complejos Atriales Prematuros/diagnóstico , Complejos Atriales Prematuros/fisiopatología , Electrocardiografía Ambulatoria/métodos , Adulto , Masculino , Adolescente , Anciano de 80 o más Años , Adulto Joven , Factores de Tiempo , Telemetría , Valor Predictivo de las Pruebas , Frecuencia Cardíaca
5.
J Obstet Gynaecol Can ; 46(9): 102612, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39004402

RESUMEN

OBJECTIVES: Little is known about whether induced abortions are associated with the final lifetime number of live births (life births). The objective of this study was to examine the association between the number of life births with the number of abortions a female has had in her lifetime. METHODS: In a national cohort design, we followed all Danish females from ages 15 to 44 years through the period 1977-2017 for induced abortions and live births. For each lifetime number of induced abortions, the average number of life births was assessed, and rates with 95% CI were calculated. RESULTS: The study included 409 497 females who completed 222 482 induced abortions and 831 742 live births. Of 265 573 (64.9%) females who did not have any induced abortion, the average number of life births was 2.09 (95% CI 2.08-2.10). For females with 1 (23.4%), 2 (7.4%), 3 (2.6%), 4 (1.0%), and ≥5 (0.7%) induced abortions during their reproductive lifespan, the average number of life births was 1.88 (1.87-1.89), 1.99 (1.98-2.00), 2.09 (2.06-2.11), 2.13 (2.09-2.15), and 2.25 (2.21-2.29), respectively. The increase in number of life births in females with 1 to females with 5+ induced abortions was 4.7% for each additional induced abortion. CONCLUSION: We found the number of induced abortions during a woman's reproductive lifespan to be positively correlated to the number of live births. This association is likely explained by a high fecundity in females with multiple pregnancies including induced abortions and suggests that even several induced abortions do not compromise a woman's general reproductive end points.


Asunto(s)
Aborto Inducido , Nacimiento Vivo , Humanos , Femenino , Adulto , Aborto Inducido/estadística & datos numéricos , Nacimiento Vivo/epidemiología , Embarazo , Adulto Joven , Estudios de Cohortes , Adolescente , Dinamarca/epidemiología
6.
Nat Med ; 30(8): 2170-2180, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38942992

RESUMEN

Metastasis occurs frequently after resection of pancreatic cancer (PaC). In this study, we hypothesized that multi-parametric analysis of pre-metastatic liver biopsies would classify patients according to their metastatic risk, timing and organ site. Liver biopsies obtained during pancreatectomy from 49 patients with localized PaC and 19 control patients with non-cancerous pancreatic lesions were analyzed, combining metabolomic, tissue and single-cell transcriptomics and multiplex imaging approaches. Patients were followed prospectively (median 3 years) and classified into four recurrence groups; early (<6 months after resection) or late (>6 months after resection) liver metastasis (LiM); extrahepatic metastasis (EHM); and disease-free survivors (no evidence of disease (NED)). Overall, PaC livers exhibited signs of augmented inflammation compared to controls. Enrichment of neutrophil extracellular traps (NETs), Ki-67 upregulation and decreased liver creatine significantly distinguished those with future metastasis from NED. Patients with future LiM were characterized by scant T cell lobular infiltration, less steatosis and higher levels of citrullinated H3 compared to patients who developed EHM, who had overexpression of interferon target genes (MX1 and NR1D1) and an increase of CD11B+ natural killer (NK) cells. Upregulation of sortilin-1 and prominent NETs, together with the lack of T cells and a reduction in CD11B+ NK cells, differentiated patients with early-onset LiM from those with late-onset LiM. Liver profiles of NED closely resembled those of controls. Using the above parameters, a machine-learning-based model was developed that successfully predicted the metastatic outcome at the time of surgery with 78% accuracy. Therefore, multi-parametric profiling of liver biopsies at the time of PaC diagnosis may determine metastatic risk and organotropism and guide clinical stratification for optimal treatment selection.


Asunto(s)
Neoplasias Hepáticas , Hígado , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/cirugía , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/genética , Masculino , Femenino , Persona de Mediana Edad , Anciano , Hígado/patología , Hígado/metabolismo , Biopsia , Estadificación de Neoplasias , Pancreatectomía , Trampas Extracelulares/metabolismo , Pronóstico
7.
iScience ; 27(4): 109610, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38632993

RESUMEN

Immune tolerance fails in autoimmune polyendocrine syndrome type 1 (APS-1) because of AIRE mutations. We have used single cell transcriptomics to characterize regulatory T cells (Tregs) sorted directly from blood and from in vitro expanded Tregs in APS-1 patients compared to healthy controls. We revealed only CD52 and LTB (down) and TXNIP (up) as consistently differentially expressed genes in the datasets. There were furthermore no large differences of the TCR-repertoire of expanded Tregs between the cohorts, but unique patients showed a more restricted use of specific clonotypes. We also found that in vitro expanded Tregs from APS-1 patients had similar suppressive capacity as controls in co-culture assays, despite expanding faster and having more exhausted cells. Our results suggest that APS-1 patients do not have intrinsic defects in their Treg functionality, and that their Tregs can be expanded ex vivo for potential therapeutic applications.

8.
Am J Obstet Gynecol MFM ; 6(5): 101371, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38588914

RESUMEN

BACKGROUND: Younger women with previous preeclampsia have an increased risk of coronary atherosclerosis. It is unknown if this risk is associated with the time of onset of preeclampsia. OBJECTIVE: This study aimed to investigate if women with early-onset preeclampsia have a higher risk of coronary atherosclerosis compared with women with late-onset preeclampsia, independent of other perinatal risk factors. STUDY DESIGN: A total of 911 women with previous preeclampsia aged 35 to 55 years participated in a clinical follow-up study, including clinical examination, comprehensive questionnaires, and cardiac computed tomography scan 13 years (range, 0-28) after index pregnancy. Early- and late-onset preeclampsia were defined as gestational age at delivery of <34+0 and ≥34+0 gestational weeks, respectively. The primary outcome of the study was the presence of coronary atherosclerosis on the cardiac computed tomography. A logistic regression analysis was performed to investigate the association between time of onset of preeclampsia, perinatal risk factors, and the primary outcome. RESULTS: Women with early-onset preeclampsia (N=139) were older (46.2±5.7 vs 44.4±5.5 years; P<.001), more likely to have hypertension (51.1% vs 35.1%; P≤.001), and had a higher body mass index (27.9±6.3 vs 26.9±5.5 kg/m2; P=.051) compared with women with late-onset preeclampsia (N=772) at follow-up. The prevalence of the primary outcome (coronary atherosclerosis) on the cardiac computed tomography among women with early- and late-onset preeclampsia was 28.8% vs 22.2%, respectively (P=.088; adjusted odds ratio, 1.74; 95% confidence interval, 1.01-3.01; P=.045 after adjustment for maternal age at index pregnancy, prepregnancy body mass index, parity, diabetes in pregnancy, smoking in pregnancy, offspring birthweight and sex, and follow-up length). CONCLUSION: Women with early-onset preeclampsia had a slightly higher risk of coronary atherosclerosis compared with women with late-onset preeclampsia. However, according to the current evidence, it does not seem indicated to limit screening, diagnostic, and preventive measures for cardiovascular disease only to women with early-onset preeclampsia.


Asunto(s)
Enfermedad de la Arteria Coronaria , Preeclampsia , Humanos , Femenino , Embarazo , Preeclampsia/epidemiología , Preeclampsia/diagnóstico , Adulto , Enfermedad de la Arteria Coronaria/epidemiología , Enfermedad de la Arteria Coronaria/diagnóstico , Estudios de Seguimiento , Persona de Mediana Edad , Factores de Riesgo , Índice de Masa Corporal , Edad Gestacional , Tomografía Computarizada por Rayos X/métodos , Modelos Logísticos
9.
J Anim Ecol ; 93(4): 393-405, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38100230

RESUMEN

Comprehending symbiont abundance among host species is a major ecological endeavour, and the metabolic theory of ecology has been proposed to understand what constrains symbiont populations. We parameterized metabolic theory equations to investigate how bird species' body size and the body size of their feather mites relate to mite abundance according to four potential energy (uropygial gland size) and space constraints (wing area, total length of barbs and number of feather barbs). Predictions were compared with the empirical scaling of feather mite abundance across 106 passerine bird species (26,604 individual birds sampled), using phylogenetic modelling and quantile regression. Feather mite abundance was strongly constrained by host space (number of feather barbs) but not by energy. Moreover, feather mite species' body size was unrelated to the body size of their host species. We discuss the implications of our results for our understanding of the bird-feather mite system and for symbiont abundance in general.


Asunto(s)
Enfermedades de las Aves , Infestaciones por Ácaros , Ácaros , Passeriformes , Animales , Filogenia , Tamaño Corporal , Infestaciones por Ácaros/veterinaria
10.
BJS Open ; 7(5)2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37837353

RESUMEN

BACKGROUND: A trial of initial non-operative management is recommended in stable patients with adhesional small bowel obstruction. However, recent retrospective studies have suggested that early operative management may be of benefit in reducing subsequent recurrences. This study aimed to compare recurrence rates and survival in patients with adhesional small bowel obstruction treated operatively or non-operatively. METHODS: This was a prospective cohort study conducted at six acute hospitals in Denmark, including consecutive patients admitted with adhesional small bowel obstruction over a 4-month interval. Patients were stratified into two groups according to their treatment (operative versus non-operative) and followed up for 1 year after their index admission. Primary outcomes were recurrence of small bowel obstruction and overall survival within 1 year of index admission. RESULTS: A total of 201 patients were included, 118 (58.7 per cent) of whom were treated operatively during their index admission. Patients undergoing operative treatment had significantly better 1-year recurrence-free survival compared with patients managed non-operatively (operative 92.5 per cent versus non-operative 66.6 per cent, P <0.001). However, when the length of index admission was taken into account, patients treated non-operatively spent significantly less time admitted to hospital in the first year (median 3 days non-operative versus 6 days operative, P <0.001). On multivariable analysis, operative treatment was associated with decreased risks of recurrence (HR 0.22 (95 per cent c.i. 0.10-0.48), P <0.001) but an increased all-cause mortality rate (HR 2.48 (95 per cent c.i. 1.13-5.46), P = 0.024). CONCLUSION: Operative treatment of adhesional small bowel obstruction is associated with reduced risks of recurrence but increased risk of death in the first year after admission. REGISTRATION NUMBER: NCT04750811 (http://www.clinicaltrials.gov).prior (registration date: 11 February 2021).


Asunto(s)
Obstrucción Intestinal , Humanos , Hospitalización , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Tiempo de Internación , Estudios Prospectivos , Estudios Retrospectivos
11.
Animals (Basel) ; 13(18)2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37760320

RESUMEN

Recognizing, assessing, and responding to threats is critical for survival in the wild. Birds, especially in their role as parents, must decide whether to flee or delay flight when threatened. This study examines how age, reproductive stage, and the presence of a mate influence flight initiation distance (FID) and nest recess duration in white storks. Analyzing the data with a generalized additive mixed model (GAMM), we found significant correlations between FID and age, reproductive stage, and presence of a mate. These results suggest that the trade-off between current and future reproduction shifts during critical breeding periods, such as incubation and nestling care. To increase breeding success, White Storks appear willing to take risks and extend their stay in the nest when offspring are most valuable and vulnerable. In the presence of a mate, individuals leave the nest earlier, suggesting possible sexual conflict over parental care. The duration of nest abandonment is consistent with FID, except for age. These results illustrate how parental age, brood value, vulnerability, and sexual dynamics influence white stork flight decisions in complex ways. Understanding these dynamics enriches our knowledge of bird behavior and adaptations to environmental challenges and highlights the complexity of parental decision making.

12.
Nat Cell Biol ; 25(9): 1254-1264, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37580388

RESUMEN

Lysosomes are catabolic organelles that govern numerous cellular processes, including macromolecule degradation, nutrient signalling and ion homeostasis. Aberrant changes in lysosome abundance are implicated in human diseases. Here we outline the mechanisms of lysosome biogenesis and turnover, and discuss how changes in the lysosome pool impact physiological and pathophysiological processes.


Asunto(s)
Lisosomas , Orgánulos , Humanos , Lisosomas/metabolismo , Homeostasis , Transducción de Señal , Autofagia/fisiología
13.
iScience ; 26(7): 107084, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37346050

RESUMEN

A hallmark of patients with autoimmune polyendocrine syndrome type 1 (APS-1) is serological neutralizing autoantibodies against type 1 interferons (IFN-I). The presence of these antibodies has been associated with severe course of COVID-19. The aims of this study were to investigate SARS-CoV-2 vaccine tolerability and immune responses in a large cohort of patients with APS-1 (N = 33) and how these vaccinated patients coped with subsequent infections. We report that adult patients with APS-1 were able to mount adequate SARS-CoV-2 spike-specific antibody responses after vaccination and observed no signs of decreased tolerability. Compared with age- and gender-matched healthy controls, patients with APS-1 had considerably lower peak antibody responses resembling elderly persons, but antibody decline was more rapid in the elderly. We demonstrate that vaccination protected patients with APS-1 from severe illness when infected with SARS-CoV-2 virus, overriding the systemic danger of IFN-I autoantibodies observed in previous studies.

14.
G3 (Bethesda) ; 13(9)2023 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-37337692

RESUMEN

The distribution of fitness effects is a key property in evolutionary genetics as it has implications for several evolutionary phenomena including the evolution of sex and mating systems, the rate of adaptive evolution, and the prevalence of deleterious mutations. Despite the distribution of fitness effects being extensively studied, the effects of strongly deleterious mutations are difficult to infer since such mutations are unlikely to be present in a sample of haplotypes, so genetic data may contain very little information about them. Recent work has attempted to correct for this issue by expanding the classic gamma-distributed model to explicitly account for strongly deleterious mutations. Here, we use simulations to investigate one such method, adding a parameter (plth) to capture the proportion of strongly deleterious mutations. We show that plth can improve the model fit when applied to individual species but underestimates the true proportion of strongly deleterious mutations. The parameter can also artificially maximize the likelihood when used to jointly infer a distribution of fitness effects from multiple species. As plth and related parameters are used in current inference algorithms, our results are relevant with respect to avoiding model artifacts and improving future tools for inferring the distribution of fitness effects.


Asunto(s)
Modelos Genéticos , Selección Genética , Mutación , Probabilidad , Aptitud Genética
15.
Front Cell Infect Microbiol ; 13: 1146431, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37234777

RESUMEN

Streptococcus pyogenes causes a multitude of local and systemic infections, the most common being pharyngitis in children. Recurrent pharyngeal infections are common and are thought to be due to the re-emergence of intracellular GAS upon completion of antibiotic treatment. The role of colonizing biofilm bacteria in this process is not fully clear. Here, live respiratory epithelial cells were inoculated with broth-grown or biofilm bacteria of different M-types, as well as with isogenic mutants lacking common virulence factors. All M-types tested adhered to and were internalized into epithelial cells. Interestingly, internalization and persistence of planktonic bacteria varied significantly between strains, whereas biofilm bacteria were internalized in similar and higher numbers, and all strains persisted beyond 44 hours, showing a more homogenous phenotype. The M3 protein, but not the M1 or M5 proteins, was required for optimal uptake and persistence of both planktonic and biofilm bacteria inside cells. Moreover, the high expression of capsule and SLO inhibited cellular uptake and capsule expression was required for intracellular survival. Streptolysin S was required for optimal uptake and persistence of M3 planktonic bacteria, whereas SpeB improved intracellular survival of biofilm bacteria. Microscopy of internalized bacteria showed that planktonic bacteria were internalized in lower numbers as individual or small clumps of bacteria in the cytoplasm, whereas GAS biofilm bacteria displayed a pattern of perinuclear localization of bacterial aggregates that affected actin structure. Using inhibitors targeting cellular uptake pathways, we confirmed that planktonic GAS mainly uses a clathrin-mediated uptake pathway that also required actin and dynamin. Clathrin was not involved in biofilm internalization, but internalization required actin rearrangement and PI3 kinase activity, possibly suggesting macropinocytosis. Together these results provide a better understanding of the potential mechanisms of uptake and survival of various phenotypes of GAS bacteria relevant for colonization and recurrent infection.


Asunto(s)
Infecciones Estreptocócicas , Streptococcus pyogenes , Humanos , Streptococcus pyogenes/genética , Serogrupo , Virulencia , Actinas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Células Epiteliales/microbiología , Biopelículas , Factores de Virulencia/metabolismo , Infecciones Estreptocócicas/microbiología
16.
Eur J Pain ; 27(7): 912-921, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37167415

RESUMEN

BACKGROUND: Stroke lesions might alter pain processing and modulation by affecting the widely distributed network of brain regions involved. We aimed to compare pain tolerance in stroke survivors and stroke-free persons in the general population, with and without chronic pain. METHODS: We included all participants of the sixth and seventh wave of the population-based Tromsø Study who had been tested with the cold pressor test (hand in cold water bath, 3°C, maximum time 106 s in the sixth wave and 120 s in the seventh) and who had information on previous stroke status and covariates. Data on stroke status were obtained from the Tromsø Study Cardiovascular Disease Register and the Norwegian Stroke Register. Cox regression models were fitted using stroke prior to study attendance as the independent variable, cold pressor endurance time as time variable and hand withdrawal from cold water as event. Statistical adjustments were made for age, sex, diabetes, hypertension, hyperlipidaemia, body mass index and smoking. RESULTS: In total 21,837 participants were included, 311 of them with previous stroke. Stroke was associated with decreased cold pain tolerance time, with 28% increased hazard of hand withdrawal (hazard ratio [HR] 1.28, 95% CI 1.10-1.50). The effect was similar in participants with (HR 1.28, 95% CI 0.99-1.66) and without chronic pain (HR 1.29, 95% CI 1.04-1.59). CONCLUSIONS: Stroke survivors, with and without chronic pain, had lower cold pressor pain tolerance, with possible clinical implications for pain in this group. SIGNIFICANCE: We found lower pain tolerance in participants with previous stroke compared to stroke-free participants of a large, population-based study. The association was present both in those with and without chronic pain. The results may warrant increased awareness by health professionals towards pain experienced by stroke patients in response to injuries, diseases and procedures.


Asunto(s)
Dolor Crónico , Diabetes Mellitus , Accidente Cerebrovascular , Humanos , Dolor Crónico/epidemiología , Umbral del Dolor , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/epidemiología , Noruega/epidemiología
17.
J Intern Med ; 294(1): 96-109, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37151110

RESUMEN

BACKGROUND: Autoimmune Addison's disease (AAD) is the most common cause of primary adrenal insufficiency (PAI). Despite its exceptionally high heritability, tools to estimate disease susceptibility in individual patients are lacking. We hypothesized that polygenic risk score (PRS) for AAD could help investigate PAI pathogenesis in pediatric patients. METHODS: We here constructed and evaluated a PRS for AAD in 1223 seropositive cases and 4097 controls. To test its clinical utility, we reevaluated 18 pediatric patients, whose whole genome we also sequenced. We next explored the individual PRS in more than 120 seronegative patients with idiopathic PAI. RESULTS: The genetic susceptibility to AAD-quantified using PRS-was on average 1.5 standard deviations (SD) higher in patients compared with healthy controls (p < 2e - 16), and 1.2 SD higher in the young patients compared with the old (p = 3e - 4). Using the novel PRS, we searched for pediatric patients with strikingly low AAD susceptibility and identified cases of monogenic PAI, previously misdiagnosed as AAD. By stratifying seronegative adult patients by autoimmune comorbidities and disease duration we could delineate subgroups of PRS suggesting various disease etiologies. CONCLUSIONS: The PRS performed well for case-control differentiation and susceptibility estimation in individual patients. Remarkably, a PRS for AAD holds promise as a means to detect disease etiologies other than autoimmunity.


Asunto(s)
Enfermedad de Addison , Adulto , Humanos , Niño , Autoanticuerpos , Autoinmunidad , Factores de Riesgo , Predisposición Genética a la Enfermedad
18.
Methods Mol Biol ; 2674: 3-32, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37258957

RESUMEN

Most pathobionts of the respiratory tract form biofilms during asymptomatic colonization to survive and persist in this niche. Environmental changes of the host niche, often resulting from infection with respiratory viruses, changes of the microbiota composition, or other host assaults, can result in biofilm dispersion and spread of bacteria to other host niches, resulting in infections, such as otitis media, pneumonia, sepsis, and meningitis. The niches that these bacteria encounter during colonization and infection vary markedly in nutritional availability and contain different carbon sources and levels of other essential nutrients needed for bacterial growth and survival. As these niche-related nutritional variations regulate bacterial behavior and phenotype, a better understanding of bacterial niche-associated metabolic activity is likely to provide a broader understanding of bacterial pathogenesis. In this chapter, we use Streptococcus pneumoniae as a model respiratory pathobiont. We describe methods and models used to grow bacteria planktonically or to form biofilms in vitro by incorporating crucial host environmental factors, including the various carbon sources associated with specific niches, such as the nasopharynx or bloodstream. We then present methods describing how these models can be used to study bacterial phenotypes and their association with metabolic energy production and the generation of fermentation products.


Asunto(s)
Otitis Media , Infecciones Neumocócicas , Humanos , Infecciones Neumocócicas/microbiología , Plancton , Streptococcus pneumoniae/genética , Biopelículas
19.
J Biol Chem ; 299(4): 104607, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36924944

RESUMEN

The glycolipid transfer protein (GLTP) has been linked to many cellular processes aside from its best-known in vitro function as a lipid transport protein. It has been proposed to act as a sensor and regulator of glycosphingolipid homeostasis in cells. Furthermore, through its previously determined interaction with the endoplasmic reticulum membrane protein VAP-A (vesicle-associated membrane protein-associated protein A), GLTP may also be involved in facilitating vesicular transport in cells. In this study, we characterized the phenotype of CRISPR/Cas9-mediated GLTP KO HeLa cells. We showed that motility, three-dimensional growth, and cellular metabolism were all altered by GLTP knockout. Expression of a GLTP mutant incapable of binding VAP disrupted cell spheroid formation, indicating that the GLTP-VAP interaction is linked to cellular adhesion, cohesion, and three-dimensional growth. Most notably, we found evidence that GLTP, through its interaction with VAP-A, affects vesicular trafficking, marking the first cellular process discovered to be directly impacted by a change in GLTP expression.


Asunto(s)
Transporte Biológico , Proteínas Portadoras , Membrana Celular , Humanos , Transporte Biológico/genética , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Membrana Celular/metabolismo , Células HeLa , Técnicas de Inactivación de Genes , Unión Proteica/genética , Regulación de la Expresión Génica/genética , Citosol/metabolismo , Movimiento Celular/genética
20.
J Biol Chem ; 299(5): 104644, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36965617

RESUMEN

The mechanistic target of rapamycin complex 1 (mTORC1) is a central regulator of mammalian cell growth that is dysregulated in a number of human diseases, including metabolic syndromes, aging, and cancer. Structural, biochemical, and pharmacological studies that have increased our understanding of how mTORC1 executes growth control often relied upon purified mTORC1 protein. However, current immunoaffinity-based purification methods are expensive, inefficient, and do not necessarily isolate endogenous mTORC1, hampering their overall utility in research. Here we present a simple tool to isolate endogenous mTORC1 from various cellular sources. By recombinantly expressing and isolating mTORC1-binding Rag GTPases from Escherichia coli and using them as affinity probes, we demonstrate that mTORC1 can be isolated from mouse, bovine, and human sources. Our results indicate that mTORC1 isolated by this relatively inexpensive method is catalytically active and amenable to scaling. Collectively, this tool may be utilized to isolate mTORC1 from various cellular sources, organs, and disease contexts, aiding mTORC1-related research.


Asunto(s)
Biotecnología , Diana Mecanicista del Complejo 1 de la Rapamicina , Proteínas de Unión al GTP Monoméricas , Proteínas Recombinantes , Animales , Bovinos , Humanos , Ratones , Mamíferos/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/química , Diana Mecanicista del Complejo 1 de la Rapamicina/aislamiento & purificación , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Proteínas de Unión al GTP Monoméricas/química , Proteínas de Unión al GTP Monoméricas/genética , Proteínas de Unión al GTP Monoméricas/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Escherichia coli/genética , Biotecnología/métodos , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Modelos Moleculares
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